Data storage system controllers often implement devices employing various communication protocols. Typically, host controllers implementing serial SCSI devices may also support serial ATA devices as well. A dual protocol capability may allow for hybrid systems with increased transactional performance offered by SCSI based drives while permitting back-up redundancy from lower cost serial ATA drives. As a result, the host controller includes a physical connection interface for both serial SCSI and serial ATA as well as the individual circuitry associated with the communication protocols for the different standards. The inclusion of circuitry for both serial SCSI and serial ATA requires additional chipset space thus increasing die size during manufacture and the expense associated with having a dual physical connection/communication protocol system. Furthermore, the complexity of a dual circuit system increases the cost of the host controller. Additionally, with the inclusion of both serial SCSI and serial ATA circuitry, the integration of devices implementing these protocols occurs at a higher level logic than if only one type of device is implemented. As a result, the higher level circuitry is required to handle the integration of data which-in-turn may effect data transfer performance in comparison to a single protocol controller.
Serial SCSI implements connections during communication between the host/device (initiator/target). Connections include a serial SCSI protocol (SSP), SCSI management protocol (SMP) and serial ATA tunneled protocol (STP). In contrast, during serial ATA communication, the host and device do not establish a connection as is done with SAS communication.
Therefore, it would be desirable to provide a method and system for emulating SAS connection for utilization with SATA devices/communication.